Cooling device for tires



l, w34. R, GOLLERT COOLING'DEVICE FOR TlREs Filed March 14, 1932 Patented May 1, 1934 COOLING DEVICE FOR TIRES Reinhold Generi, Berlin-Charlottenburg, Germany AppiicationfMa'reh 14, 1932, serial No. 598,708 In Germany March 14, 1931 3 Claims.

The object of the invention is, to prevent excessive heating ofthehollow tiresof automobiles by continually cooling the walls of the hollow space.

5 The known endeavours of this kind, when a liquid filling was used, could not attain this object, because the enclosed liquid, surrounded by rubber, could not radiate the absorbed heat. The employment of metallic heat conductors was l0 however useless, because these did not absorb sufcient heat from the walls of thehollow space. Their surfaces could only have a slight Contact with the rubber surfaces to be cooled; the air otherwise surrounding them was an insulator.

The invention employs a pliable, preferably filling material capable to ow for moistening the walls of the hollow space and therefore for completely absorbing the heat which they have to give up. Moreover, the many times greater conductivity of this material, as compared with that ofthe rubber, is utilized for accelerating.

the transmission of the heat absorbed to metallic conductors, the surfaces of which for absorbing the heat can be smaller in the same proportion as the inner walls of the rubber `body radiating the heat.

As metallic conductors possess 11000 times better conducting properties than rubber, very small cross sections are sucient for conducting olf the entire quantity of heat absorbed. It is preferable, however, for relatively large surfaces of themetallic conductors to be in permanent or periodical contact with the filling lquid,in order to act immediately the heating commences and to prevent steam generation.

Consequently, the invention relates to the employment of several bodies having different properties and conductivities; some of these bodies serving for absorbing and accumulating the heat to be given up by the Walls of the hollow space and others for conducting off the collected heat to the outer side of the tire.

The main advantages derived from this combination according to the invention are:-

l. The possibility of employing any type of hollow tire.

. 2 The effect commences immediately at the beginning of travel before steam develops, thus resulting in saving the material, a longer life and less Wear of the tire.

3. Continuous cooling, complete absorption and conducting off of the heat.

l 4. More rapid cooling during pauses in traveleil) iso

5. Smaller filling quantity, therefore no decrease in elasticity.

6. No failure when in operation, no attendance, no endangering of fittings or of the tire.

7. Cheap and easy to produce and fit.

In tires for lower stressing, Which are shrunk on a steel band, it is sufficient to provide recesses in the foot of the rubber body, which allow the exposed surfaces of the steel band to come into Contact with the liquid and thus utilize the steel band for conducting off the heat to the wheel body. 'Ihe contacting of the liquid and the steelband may be eected by the progressively moving Wave which is produced in the liquid when the vehicle is travelling, owing to the compression of the rubber body under the load.

It is preferable, to insert metal plugs in the tire foot, which plugs project into the hollow space and are fitted with large surface structures, such as Wire brushes, cords, plates and the like, in X5 order to offer suitably large absorbing surfaces to the liquid ushing the same. In the case of pneumatic tires such elements can be fitted in the inner tube in a similar manner as the valve. These elements may also be made with a large surface on the outer surface for better conducting olf to bad conductors.

Two embodiments of the invention are illustrated by way of example in the accompanying drawing in which:-

Fig. 1 shows in cross section a pneumatic tire with a. metal bundle.

Fig. 2 is a part longitudinal section of a hollow tire with a cord.

In Fig. l a designates the rim, b the outer cover,A c the inner tube and d the liquid which, when the wheel is rotating, is situated radially beyond the centre of the outer cover owing to the action of the centrifugal force. ,f and g are the lower and upper parts respectively of a screw connection, which extends through the inner tube c and clamps and packs the hole between the flanges f and The flange f is pressed against the rim, and the foot h. of a wire bundle h is inserted in the upper part g, the free end of this bundle extending up to the inner wall of the inner tube c, so that the liquid is always in contact with the wire bundle.

In Fig. 2 a cordz' is provided instead of the wire bundle. The free end of this cord extends into the hollow space, whereas its end i is mounted in a metal fooi; m, which is inserted into the steel band 11.; the cord or its foot extends through the rubber layers .o and p, and a packing ring 1' is clamped between the metal foot m and the wall of 11@ This device therefore effects the cooling within' generating of steam.

I claim:-

1. A motor Vehicle tire with filling of cooling liquid comprising metallic conductors extending into the hollow space of the tire and dipping into the cooling liquid to absorb from said liquid the heat taken up by the liquid whilst the vehicle is travelling and when it is at a standstill and to conduct this absorbed heat to the outside of the tire.

2. A motor vehicle tire as specified in claim 1, comprising in combination with the wheel rim and the heat conducting element, a foot on said rim carrying said heat conducting element adapted to indirectly establish heat communication between the interior of the tire and the atmosphere.

3. A motor Vehicle tire as specied in claim 1, comprising in combination with the heat conducting element and the rim of the Wheel, a steel band on said rim, and a foot carrying said heat conducting element extending through said steel band Vand said rim adapted to directly establish heat communication between the interior of the tire and the atmosphere.'

REINHOLD GOLLERT. 

